Definition: You are given a math word problem and you are supposed to only use subtraction on the numbers embedded in the text to answer the following question and then only report the final numerical answer.
Input: Context: A book has 3 chapters. The first chapter is 91 pages long the second chapter is 23 pages long and the third chapter is 25 pages long. 

 Question: How many more pages does the first chapter have than the second chapter?

68